Pressure indicating and relieving device



B. WILLACH PRESSURE INDICATING AND RELIEVING DEVICE Sept. 12, 1950 Filed Dec. 5, 1945 I I II VIII I I I a 7 l l i av H\\. 5 1 x w r v 1% w M WW n m/fififlfi ifi Patented Sept. 12, 1950 PRESSURE INDICATING AND RELIEVING DEVICE.

Bernhard Willach, Chicago, Ill., assignor to Jas. P. Marsh Corporation, Chicago, 111., a corpora.-

tion of Illinois Application December 3, 1945, Serial No. 632,429

Claims.

The present invention relates to a combined pressure-indicating and relieving device and has special reference to a unitary device which may be connected, through a single opening, to a pressure system for indicating the pressure within the system and maintaining it below a predetermined maximum or relieving it to any extent desired.

More particularly this invention pertains to a device having a pressure responsive element, an indicator associated therewith operable by the pressure responsive element and automatically as well as manually actuated fluid pressure control and release means.

The device of the present invention is capable of wide application in steam or other fluid pressure systems and apparatus. One example of its use is in connection with pressure cookers where it indicates the pressure of the steam or vapor within the cooker, automatically prevents the fluid pressure from rising above a predetermined maximum and permits the exhausting of the pressure when the cooking has been completed or whenever desired. By means of the automatic fluid pressure release means or valve and the proper adjustment of the heating element for the cooker or other fluid pressure system, the pressure within the cooker or other fluid pressure system may be maintained within close limits. If desired an audible signal or alarm may also be incorporated which is actuated when the fluid under pressure is relieved through the automatic relief valve.

It is an object of this invention to provide a unitary device for connection to a pressure system or apparatus which will clearly indicate the fluid pressure within the system and provide for the control and relief of the fluid pressure there- 1n.

Another object is to provide a combined pressure indicating and relieving device which will automatically prevent the increase of the fluid pressure in the system or apparatus to which it is connected above a predetermined amount.

A further object is to provide such a device which will sound an audible signal as soon as the maximum fluid pressure has been exceeded.

A still further object is to provide a device of the type referred to above which will permit the pressure to be exhausted to the atmosphere when and to the extent desired.

Further objects and advantages will be apparent from the following description and the appended claims when considered with the attached drawings in whichis inserted in the opening ll.

Figure 1 is an elevational View of a combined pressure indicating and relieving device embodying the present invention;

Fig. 2 is a view similar to Fig. l with the cover and dial or face removed;

Fig. 3 is a cross sectional view partially in elevation taken along the lines 3-3 of Fig. 1;

Fig. 4 is a view of the device partially inserted in the housing provided therefor; and

Fig. 5 is a bottom plan view of the housing and the dial.

Referring more particularly to the drawings, there is shown a preferred embodiment of the present invention comprising a post I which may be hexagonally shaped in cross section with the lower end 2 threaded for insertion into a threaded opening in a fluid pressure system or apparatus. Extending longitudinally through the post I is central opening 3 which is enlarged adjacent the upper or outer end of the post to provide space for a safety valve assembly. The upper end of the post is tapped to receive a threaded plug 4 which seals the end of the passageway 3.

One type of safety valve which may be employed is shown in Fig. 3. Between the narrow and wide portions of the passageway, there is formed a valve seat 5 for receiving a ball valve 6. A coil spring I connected to the inner or lower side of the plug 3 tends to maintain the ball valve 6 on its seat 5 to close off the wide portion of the passageway 3 from the narrow portion thereof. The tension on the spring 1 may be altered to adjust the valve by turning the plug 4 in the post I.

A tapped opening 8 is provided in the rear side of the post I so as to communicate with the enlarged portion of the passageway 3 between the plug 4 and the ball valve 6. A tubular outlet element 9 having an inner threaded end of reduced diameter is screwed into the tapped opening 8 to connect the enlarged portion. of the passageway 3 with the atmosphere. If desired a reed ID may be mounted in the tubular outlet element 9 so that when fluid escapes from the enlarged portion of the passageway 3 through the outlet element 9 a whistle or other audible sound will result.

A manually operated valve is preferably provided to permit the relief of pressure from the passageway 3 on the pressure side of the safety valve. For this purpose a hole II is tapped in the post I preferably in the rear side thereof and communicates with the passageway 3 through a bore 12 of smaller diameter. A tubular plug l3 This plug [3 is internally threaded to receive a screw valve M which may be provided with a conical inner end to seal off the bore l2 from the opening II. In order to permit the fluid under pressure to es-' cape past the valve M a longitudinal slot is provided in the inner surface of the plug [3. Thus, when the valve 14 is threaded into the 'plug so that the conical end engages the bore 12, no fluid can escape from the passageway 3 through the bore. However, when the valve I4- is unscrewed the fluid under pressure within the passageway 3 may escape through the bore 12 and the slot 15. A blowout valve i6 is also mounted in the post I and connects with the passageway 3 below the valve I4.

With the construction above described the plug 4 is adjusted to provide the proper tension on the spring 8 to maintain the ball valve 6' seated in the valve seat 5 until a predetermined maximum fluid pressure has been reached. At thistime the ball valve iiwillbe raised permitting the-fluidin the narrow section of the passageway 3 to enter the enlarged portion of the passageway and escape through the outlet element 9to the atmosphere. At the same time the reed Ill will be vibrated to make an audible signal; As soon as the fluid pressure drops below the predetermined maximum the valve is closed by the spring 'i and prevents further escape of the fluid pressure. valve fails to operate, the blowout valve will function and, prevent the pressure from getting too high. In addition to these automatic pressure control means the valve l4 may be manu- If for any reason the safety ally operated to relieve the pressure entirely or to any extent desired.

The pressure indicating means of the device may comprise a Bourdon tube 2b which has one end brazed in the post i and in. communication with the reduced portion of the passageway 3.

The opposite end of the Bourdon tube is closed and isprovided with a connecting post ii to which one end of a link 22 is pivotally connected. The opposite end of the link 22 is pivotally connected to the U-shaped extension 230i the indicating hand 24 which is mounted about the. pin

25 secured in the front face of the post i.

When the pressure within the passageway 3 and the Bourdon tube is increased, the tube tends-to straighten out, which moves the link 22 outwardly away from the post land causes the indicating hand 24 to be moved in a direction to show the increase in pressure. The link 22. is provided with a U bend so that its length may be quickly altered to adjust the position of the indicating arm 24.

Secured to the front of the post i is a-face or dial 25a preferably having two substantally parallel ofiset portions '26 and 21 connected by. a shelf 28-. The upper portion 26 of the dial 25ais secured against the upper face of the post i by meansv of a screw '29 while the lower portion 2'!- is spaced from the post and overlies the pin 25 to which the indicating arm 2t is pivoted. The indicating arm passes upwardly through a slot 30 in the shelf 28. This construction permits the use of a relatively long indicating arm so that the free end moves a substantial distance with slight changes in pressure in the Bourdon tube 20. Consequently, relatively large indicating figures may be employed on the dial. At: the same time the operating portions of. the deviceare concealed.

A dished housing 3| having a hexagonal opening 32 through which the post I may be passed 4. is provided for the device. The housing 3! has openings 33 and. 34 which register with the tapped holes 8 and H in the post I. They are slightly larger in diameter than the diameters of the tapped openings 8 and H but of smaller diameter than the outer portions of the tubular outlet element 9 and the plug l3. To insert the device in the casing 31, the post 1' is passed through the opening 32 as shown particularly in Fig, 4 and then when the rear side of the post i is against the rear of the casing St the tubular outlet 9- is threaded-into the tapped opening 3 and clamp the housing between the enlarged outer portion of the outlet and the post. In the same manner the plug 13 further secures the housing 3! to the rear of the post i. After the device is mounted in the housing 3 I, a cover glass 35' is placed over the dial 25a and is held in place by a removable rim 1%.

In order to accurately position the face or dial 250; on the post 2| the dial is provided with a flange 3'! which is indented and shaped to fit about aportion of the post I. thus properly positioned while the screw 29 is insertedto secure it firmly to the post i.

In a. combined gauge and safety deviceas above described, the device itselfmay be easily,

quickly and accurately assembled, and onlya single opening is required to attachit to a fluid pressure system. When attached to a fluid pressure, system it indicates the pressure of the fluid within the system and. also prevents the fl'ui'd" pressure from rising above a predetermined maximum by permitting the escape of the fluid whenever the maximum has been exceeded. At the same time the fluid pressure within. the system may be discharged" by means of" the manually operated valve 14.

While I have shown and described a particular embodiment of the present invention it is manifest that changes and modifications may be resorted to without departing from the spirit and" scope of the appended claims.

I. claim:

1. A combined pressure gauge and safety valve comprising a post having a fluid pressure passageway therein for connection to a fluid pressure system, a fluid pressure operated safety valve positioned adjacent the outer end of said passageway for normally closing the same, .pressure indicating means actuated by the fiuidi pressure in said passageway, a dished housing.

for said'post, safety valve, and pressure indicating means, and atubular outlet element removably secured to said post and in communication with said-passageway on the outlet side of said safety valve, said outlet element passing through said housing and having, a shoulder for clamping.

said housing between said shoulder and said Post.

2-. Acombined. pressure gauge. and'safety valve comprising a post having a fluid pressure passageway therein for. connection to a fluid pressure system, a fluid pressure operated safety valve positioned adjacent the outer end of. said passageway for normallyclosing the same, pressure indicating means actuated by the fluidpressurein saidpassageway, a dished housing for said post, safety valve, and pressure indicatingmeans, and a tubular outlet element-removably secured to said post and in communication with-said passageway. on-the outlet side-of said safety valve, said outletelement passing through said housing and having a shoulder for clamping said housing between said shoulder and said post,

The dial may be.

and said tubular outlet element having audible signal means therein for being actuated by the fluid pressure passing therethrough.

3. A combined pressure gauge and safety valve comprising a post having a fluid pressure passageway therein for connection to a fluid pressure system, a fluid pressure operated safety valve positioned adjacent the outer end of said passageway for normally closing the same, pressure indicating means actuated by the fluid pressure in said passageway, a dished housing for said post, safety valve, and pressure indicating means, and a tubular outlet element removably secured to said post and in communication with said passageway on the outlet side of said safety valve, said outlet element passing through said housing and having a shoulder for clamping said housing between said shoulder and said post, said pressure indicating means including a Bourdon tube having one end secured to said post and in communication with said passageway on the pressure side of said safety valve and extending over the upper end of said post.

4. In a, pressure gauge comprising a post having a fluid pressure passageway therein, a pressure indicating member pivotally mounted on said post and means actuated by the fluid pressure in said passageway connected to said indicating member for moving the same in accordance with said fluid pressure, a dial mounted adsaid portions overlying the pivoted end of said 3 indicating member and the other portion being positioned inwardly of said indicating member, and a flange on said dial shaped to fit over a portion of said. post to position said dial with respect to the remainder of said gauge.

5. A combined pressure gauge and safety valve comprising a post having a fluid pressure passageway therein for connection to a fluid pressure system, a fluid pressure operated safety valve positioned adjacent the outer end of said passageway for normally closing the same, pressure indicating means actuated by the fluid pressure in said passageway, a dished housing for said post, safety valve, and pressure indicating means, a tubular outlet element removably secured to said post and in communication with said passageway, said outlet element passing through said housing and having a shoulder for clamping said housing between said shoulder and said post, and means for normally preventing the escape of fluid through said outlet.

BERNHARD WILLACI-I.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 822,826 Coleman June 5, 1906 867,942 Bobrick Oct. 15, 1907 1,717,653 Berge June 18, 1929 1,751,867 Manuel Mar. 25, 1930 FOREIGN PATENTS Number Country Date 1,206 Great Britain Jan. 22, 1891 

